When I installed AC10, it told me that there are Work Environments from previous versions on the computer and asked me if I wanted to import them, which I answered with a Yes.
Now I have the AC9 Work Environment (WE) available to me in AC10.
It is also possible to export the AC9 WE and import it into AC10.
In AC10 ended up keeping the new menu structure (so I will learn it on the long run), but I have the same AC9 shortcuts (I usually work with shortcuts, not selecting menu items with the mouse).
This works quite well for me.
Loving Archicad since 1995 - Find Archicad Tips at x.com/laszlonagy
AMD Ryzen9 5900X CPU, 64 GB RAM 3600 MHz, Nvidia GTX 1060 6GB, 500 GB NVMe SSD
2x28" (2560x1440), Windows 10 PRO ENG, Ac20-Ac27